1. Field of the Invention
The invention pertains generally to the field of material or article handling, and more particularly to round hay bale handling. A manifestation of the present invention is mounted on a vertically swinging load support such as a common tractor three-point hitch, and incorporates a fork-type hay retainer that is laterally tiltable, and has a novel boom structure.
2. Description of the Related Art
Throughout the ages mankind has derived much benefit from animals, ranging from companionship and security from the trusted dog to a vital source of food and raw materials. While pre-historic man is thought to have been a hunter and gatherer, reliance upon random events of nature has not been accepted by mankind. Instead, people have developed ways to keep and care for animals to ensure their availability, which provides synergistic benefit to both man and animal. This is referred to as animal husbandry, which is simply caring for the needs of animals. Animal husbandry is very old, almost certainly predating any written histories.
A critical component of animal husbandry is providing a food source for the animals, regardless of the season. In many locales and climates, this will generally require the gathering and storing of food to carry the animals through inclement seasons and periods of weather. One way this is practiced is by growing a crop that is abundant beyond the immediate or short term needs of the animals during milder seasons. The excess crops are then collected or harvested for consumption or storage until needed.
In the handling of agricultural crops such as hay or straw, it is common practice to cut the crop during a first pass through the field. During a subsequent pass, the crop will be raked into windrows. After the crop has had sufficient time to dry, then it is normally baled. With older baling equipment, relatively small rectangular bales were created. These bales were commonly manually loaded onto and from trailers, and some more recent equipment assisted with such loading and unloading.
In order to further reduce the amount of labor needed to harvest a crop, and thereby improve the efficiency and lower the cost of production, machines have been developed and refined which vastly reduce the time required to accomplish the work. One of these is a hay baler that produces very heavy and large generally cylindrical hay bales. Owing to the enormous size and weight of these bales, machinery is required to lift and move the bales from the fields where they are produced. While the present invention will be described specifically with reference to hay bales, it will be understood that the present invention is not solely limited thereto. Other agricultural crops such as cotton and various kinds of straw are similarly baled. Consequently, the present invention may be applied to any baled agricultural crop, and to non-agricultural bales as well.
Many industries, including agriculture, use front-end loaders and tractors. These machines are highly versatile, including an engine for locomotion and various couplers that allow additional useful equipment to be attached thereto. Generally configured with a front end bucket which may be attached or detached to allow other equipment to be used, these machines are capable of transporting many thousands of pounds of materials. Most loaders are capable of maneuvering about in relatively small spaces, further adding to their versatility. The bucket is useful for scooping from large piles or smooth surfaces, and so may be used not only for moving materials about but also for cleaning up surfaces.
A common agricultural tractor will also typically have or may readily be provided with a three-point hitch which is designed to connect a variety of implements to the tractor. The three-point hitch typically supports the implements by coupling through two lower links or lift arms that are on opposed sides of the longitudinal and vertical center plane of the tractor, and an upper link or stabilizer arm that is located within the vertical center plane of the tractor and defines the third hitching point. This type of hitch will also typically have one or more hydraulic cylinders that permit the operator to raise the three-point hitch. Most also include a hydraulic cylinder that enables the operator to control the fore and aft tilt of the implement. Some of these three-point hitches require specific pinning or coupling to the implement, while others are of the quick-attaching or quick-coupling type. Exemplary United States patents illustrating three-point hitches, the teachings and contents which are incorporated herein by reference, include: U.S. Pat. No. 4,210,209 by van der Lely, entitled “Agricultural implement”; U.S. Pat. No. 4,236,613 by van der Lely, entitled “Coupling member”; and U.S. Pat. No. 5,029,650 by Smit, entitled “Adjustable quick attaching hitch coupler”.
Other United States patents illustrate three-point hitches and apparatus to transport a single bale, the teachings and contents which are incorporated herein by reference, including: U.S. Pat. No. 4,027,773 by Kenworthy, entitled “Baled hay loading and transport device”; U.S. Pat. No. 4,161,253 by Ralston et al, entitled “Carrier and dispenser for cylindrical bales”; and U.S. Pat. No. 5,178,505 by Smith, entitled “Three-point hitch attachment with hay mover”. While these patents illustrate various bale handling apparatus, these apparatus are limited to supporting a single bale. As may be apparent, the ability to load two or even three bales onto a vehicle or machine can, for exemplary purposes, reduce the amount of transport time required to clear a harvested field of bales and transport the bales to a storage area to one-half or one-third of that required when transporting a single bale.
Some artisans have designed apparatus which couple with a three-point hitch and onto which two bales can be loaded. Exemplary United States patents, the teachings and contents which are incorporated herein by reference, include: U.S. Pat. No. 4,091,947 by Fischer, entitled “Tractor mounted multiple bale carrier”; U.S. Pat. No. 4,306,825 by Yilit, entitled “Round bale handling apparatus”; U.S. Pat. No. 7,182,568 by McGinnes, entitled “Bale handling apparatus”; U.S. Pat. No. 7,753,636 by Hennig, entitled “Adjustable bale mover spikes”; and U.S. Pat. No. 8,444,362 by Hennig, entitled “Round bale mover”.
The Fischer patent describes three pairs of forks, each pair which can be used to scoop under and lift a bale. While relatively unique in the ability to transport three bales on the three-point hitch, the apparatus is relatively complex. At least two of the bales, 81 and 82 in the Fischer figures, must be properly positioned adjacent to each other prior to loading. Further, critical moving components are down adjacent to the ground where these components are most likely to be damaged or contaminated with dirt and sand.
In contrast, the Yilit patent illustrates a much simpler construction having critical pivot points generally higher above the ground than the Fischer construction. However, the Yilit apparatus necessarily shifts the bales farther behind the rear wheels, substantially increasing the tendency towards rear tipping and also increasing the strength required of the bale supporting components.
The McGinnes apparatus has a most simple construction, completely avoiding moving parts other than the three-point hitch, and is capable of transporting two bales simultaneously. However, the bales cannot be selectively loaded and unloaded, since the highest main spear must be loaded first and unloaded last.
Hennig in U.S. Pat. No. 7,753,636 illustrates an apparatus coupled to a three-point hitch and capable of independently lifting two bales. However, this Hennig apparatus requires two hydraulic cylinders, one for each bale's associated pair of spears. Further, the apparatus uses linear bearings that are difficult to keep clean and lubricated and which are likely to bind and gall.
Hennig in U.S. Pat. No. 8,444,362 has provided substantial improvement over the previous apparatus, enabling the separation between an adjacent pair of bales to be variable both during loading and unloading. Unfortunately, this once again requires a plurality of hydraulic cylinders, one pair for swiveling each bale support closer to or farther from the tractor central longitudinal axis, and another pair for independent elevation control of each bale.
Of the foregoing two-bale handlers, only Hennig in U.S. Pat. No. 8,444,362 is capable of shifting a bale closer to the tractor central longitudinal axis during loading, but this is accomplished with significant complexity and the need for four hydraulic cylinders and several bearing or bushing sets. While these two-bale patents each improve upon the single bale prior art apparatus, a simpler, reliable, durable and safe two-bale lift and transport is still very much desired in the industry.
In addition to the foregoing patents, Webster's New Universal Unabridged Dictionary, Second Edition copyright 1983, is incorporated herein by reference in entirety for the definitions of words and terms used herein.